An exemplary dynamic random access memory includes a first transistor (210), a second transistor (220) and a comparator (230). The first transistor includes a first gate electrode (211), a first source electrode (213) and a first drain electrode (215). The second transistor includes a second gate electrode (221), a second source electrode (223) and a second drain electrode (225). The first source electrode is connected with the second source electrode. The first drain electrode is an input terminal for inputting a message. The comparator is connected to the second drain electrode, and preconfigured with a reference current. The comparator compares the reference current and a current through the second drain electrode to define a state of the current read from the comparator.